The repeating image

Bill and Ted, Wayne and Garth, and Beavis and Butthead all dominated pop culture right around the same time, give or take 5 years. What was it about a pair of retarded metalheads that so delighted the American teenager's soul? The fact that one was blond and the other brown haired? That they played air guitar? Had questionable tastes in music? What was it about this image that made it so appealing to teens in the early nineties that it utterly dominated our entertainment only to unceremoniously fade away? Unlike buddy cops, underdog athletes, odd couples, etc, whose day in the sun never ends, the "rocker buddies" briefly emerged as novel twist on the buddy concept, produced spin-offs, and then despite it's success...died.

This isn't so interesting in itself. Fads always die. But why did this "meme" succeed when it did, and why did it die when did? Will it mutate into a trio of Goth kids? Hip hip kids? Indie nerds? Or is there something magical about metal heads that makes us laugh?

P.S. I apologize for using the word "meme".